Yamamoto, Kazami; Kinsho, Michikazu; Hayashi, Naoki; Saha, P. K.; Tamura, Fumihiko; Yamamoto, Masanobu; Tani, Norio; Takayanagi, Tomohiro; Kamiya, Junichiro; Shobuda, Yoshihiro; et al.
Journal of Nuclear Science and Technology, 59(9), p.1174 - 1205, 2022/09
In the Japan Proton Accelerator Research Complex, the purpose of the 3 GeV rapid cycling synchrotron (RCS) is to accelerate a 1 MW, high-intensity proton beam. To achieve beam operation at a repetition rate of 25 Hz at high intensities, the RCS was elaborately designed. After starting the RCS operation, we carefully verified the validity of its design and made certain improvements to establish a reliable operation at higher power as possible. Consequently, we demonstrated beam operation at a high power, namely, 1 MW. We then summarized the design, actual performance, and improvements of the RCS to achieve a 1 MW beam.
Yano, Tsuneo*; Hasegawa, Koki*; Sato, Tatsuhiko; Hachisuka, Akiko*; Fukase, Koichi*; Hirabayashi, Yoko*
Iyakuhin Iryo Kiki Regyuratori Saiensu, 50(3), p.122 - 134, 2019/03
This report provides an overview of alpha-particle-emitting radiopharmaceuticals applied by micro-dosimetry.
Hasegawa, Takuma*; Nakata, Kotaro*; Tomioka, Yuichi*; Goto, Kazuyuki*; Kashiwaya, Koki*; Hama, Katsuhiro; Iwatsuki, Teruki; Kunimaru, Takanori*; Takeda, Masaki
Geochimica et Cosmochimica Acta, 192, p.166 - 185, 2016/11
Groundwater dating was performed simultaneously by the He and C methods in granite of the Tono area in central Japan. Groundwater was sampled at 30 packed-off sections of six 1000-m boreholes. He concentrations increased and C concentrations decreased along a groundwater flow path on a topographic gradient. He ages were calculated by using the in situ He production rate derived from the porosity, density, and U and Th content of the rock, neglecting external flux. The linear relation between the He ages and the noncorrected C ages, except in the discharge area. Simultaneous measurements make it feasible to estimate the accumulation rate of He and initial dilution of C, which cannot be done with a single method. Cross-checking groundwater dating has the potential to provide more reliable groundwater ages.
Hama, Katsuhiro; Mikake, Shinichiro; Nishio, Kazuhisa; Kawamoto, Koji; Yamada, Nobuto; Ishibashi, Masayuki; Murakami, Hiroaki; Matsuoka, Toshiyuki; Sasao, Eiji; Sanada, Hiroyuki; et al.
JAEA-Review 2014-038, 137 Pages, 2014/12
Japan Atomic Energy Agency (JAEA) at Tono Geoscience Center (TGC) is pursuing a geoscientific research and development project namely the Mizunami Underground Research Laboratory (MIU) Project in crystalline rock environment in order to construct scientific and technological basis for geological disposal of High-level Radioactive Waste (HLW). The MIU Project has three overlapping phases: Surface-based Investigation phase (Phase I), Construction phase (Phase II), and Operation phase (Phase III). The MIU Project has been ongoing the Phase II and the Phase III in fiscal year 2013. This report presents the results of the investigations, construction and collaboration studies in fiscal year 2013, as a part of the Phase II and Phase III based on the MIU Master Plan updated in 2010.
Shimada, Taihei; Yamamoto, Masanobu; Suzuki, Hiromitsu; Toda, Makoto*; Hasegawa, Katsushi*; Omori, Chihiro*; Tamura, Fumihiko; Schnase, A.; Hara, Keigo*; Nomura, Masahiro; et al.
Proceedings of 6th Annual Meeting of Particle Accelerator Society of Japan (CD-ROM), p.1080 - 1082, 2010/03
Few magnetic alloys cores of the RF cavities which are installed in the 3 GeV rapid cycling synchrotron of the J-PARC have buckled after the operation of about two years. We heated cores in the air and measured thermal deformation in order to get information about the buckling process. We report the results.
Schnase, A.; Ezura, Eiji*; Hara, Keigo*; Hasegawa, Katsushi; Nomura, Masahiro; Omori, Chihiro*; Shimada, Taihei; Suzuki, Hiromitsu; Takagi, Akira*; Tamura, Fumihiko; et al.
Proceedings of 5th Annual Meeting of Particle Accelerator Society of Japan and 33rd Linear Accelerator Meeting in Japan (CD-ROM), p.340 - 342, 2008/00
Hasegawa, Shin; Seko, Noriaki; Tabata, Kokichi*; Tamada, Masao; Katakai, Akio; Kasai, Noboru; Watanabe, Tsutomu; Kawabata, Yukiya*; Nawata, Yoshitaka; Sugo, Takanobu
JAERI-Tech 2001-020, 126 Pages, 2001/03
no abstracts in English
Hasegawa, Takuma*; Nakata, Kotaro*; Tomioka, Yuichi*; Goto, Kazuyuki*; Kashiwaya, Koki*; Hama, Katsuhiro
no journal, ,
The groundwater flow velocity is one of the important items in the safety assessment for the HLW disposal. Generally, it is too difficult to measure the groundwater flow velocity directly. Therefore, to determine the groundwater age by radio active isotopes are effective. However, there are some problems to apply the metrology to the natural samples. For example, because the ratio of Carbon isotope changes by dissolving of the carbonate mineral and resolving the organic materials, the development of the technique for correcting this is needed. In this study, the groundwater ages are measured by He and C, etc. and compared these results as a joint research with Central Research Institute of Electric Power Industry.
Iwatsuki, Teruki; Sato, Toshinori; Takeuchi, Ryuji; Onoe, Hironori; Onuki, Kenji; Saegusa, Hiromitsu; Hasegawa, Takashi; Kuroiwa, Hiroshi; Tsuyuguchi, Koji; Ikeda, Koki; et al.
no journal, ,
Closure experiment of gallery of MIU is planned to understand the recovery process of geological environments after the closure. Flooding test gallery and monitoring boreholes are designed at 500 m access gallery to observe recovery of water pressure, chemistry around cement and burial materials, rock stress. Evaluation of numerical analysis methods on hydraulic, chemical and mechanical change will be conducted based on the results of upcoming closure experiment.